George d



(No Model.)

G. D. TUCKER.

SCREW THREADING TOOL.

No. 336,024. Patenteg eb. 9; 1886.

Witnesses; fifi 9W N. PETERS, mommrw m. Wnhinglnn, 0.;

I UNITED STATES PATENT OFFICE.

GEORGE D. TUCKER, OF HARTFORD, CONNECTICUT, ASSIG-NOR TO THE PRATT &WHITNEY COMPANY, OF SAME PLACE.

SCREW-TH READING TOOL.

SPECIFICATION forming part of Letters Patent No. 336,024, dated February9, 1886.

Application filed May 25, 1885.

To all whom, it may concern;

Be it known that I, GEORGE D. TUCKER, a citizen of the United States,residing in the city and county of Hartford, and State of Connecticut,have invented certain new and use ful Improvements in Threading-Tools,of which the following is a specification, reference being had to theaccompanying drawings, forming a part thereof.

This invention relates to that class of threading-tools which arefurnished with oscillating chasers, arranged to be adjusted to a largeror smaller diameter, as the case may be, in order that the tool may bequickly withdrawn after threading a piece.

The principal object of my invention is to provide a tool ofthat classin which the chasers shall be adjustable to permit some variation in thediameter of the threads made thereby; and it is equally applicable totools for cut ting either external or internal threads by a slightmodification in the form and arrangement of the parts for holding andoperating the chassis.

The invention consists in certain combinations, which will first bedescribed in connection with the drawings and afterward pointed out inthe claims.

Figure 1 is a front View, partially in section, showing my invention asapplied to large tools for cutting external threads, such, for instance,as those on large steam and water pipes and fittings. Fig. 2 is alongitudinal sectional view of the same tool. Fig. 3 is a front view,also partially in section, of a smaller tool embodying my invention, thetool be ing especially adapted for use in screw-machines for cuttingexternal threads of smaller diameter. Fig. 4 is a longitudinal sectionalview of the tool shown in Fig. 3. Fig. 5 is a front view of a similartool for cutting internal threads. Fig. 6 is a longitudinal view,partially in section, of the form of tool shown in Fig. 5. Fig. 7 is aperspective view of one of the renewable oscillating chasers which areshown in Figs. 3 and 4.

Similar characters designate the same parts in all the figures.

In the drawings, A designates the body of the tool, which body is madein various shapes Serial No. 166,577.

(No model.)

and sizes, these being determined by the kind of work for which and theconditions under which the tool is to be used. The form of body shown inFigs. 1 and 2 is adapted to be secured to the face-plate of a lathe orpipethreading machine, while those shown in Figs. 3 to 6 generally havea shank, B, for insertion into the turret of a screw-machine. A seriesof sockets, S, usually three or more in number, are formed in the bodyA, substantially as shown in the several front views, and into thesesockets the chasers C are fitted, so as to be oscillated therein, asshown by dotted lines 5 in said front views. The circular part 2 of thesockets and chasers is inclined to the axis of the body, as clearlyshown in the sec tional views, and by lines 3 and 4 in Figs. 1, 3, and5. This circular part of the chasers constitutes a pivot on which saidchasers oscillate. The chasers are held into the sockets by a flangednut, N, Figs. 1 and 2, the flange of which, 6, rests against the frontend of said chasers, or in Figs. 3 and 4 said nut is lettered N and itssaid flange 6, but its operation is the same as in Figs. 1 and 2. .InFigs. 5 and 6 said nut is lettered N and it has there adifferently-formed flange, 6 which engages with the guard G", as in Fig.6, which guard there has a flange, 7, for that purpose. The chasers areheld forward against the flange by a nut, of which I have shown threemodifications. Thus, as in Fig. 4, it may be formed as at M, similarlyto the flanged nut N, and bear directly on the chaser. It may be formedintegrally with nut N", and also bear against the chaser directly, as inFig. 6, or it may be a separate nut, P, and bear against the guard G,this being soinade as to bear against the chasers, as in Fig. 2. Asshown in Fig. 6, the nut N is made in two parts for convenience inputting together the parts of the tool, the parts of said nut being heldtogether by screws 8 in the usual manner. Guard G has slots, as shownbest in the front views, through which the threaded parts 10 of thechasers 9 project. These slots fit the chasers closely, so

that by turning the guard said chasers may be thrown into their workingposition 10, or into their idle or open position 5, as may be Foreffecting that result, the body desired.

A may be slotted, as at 11, and a handle, H, inserted through said slotinto guard G or G. When the nut is not so made as to hold guard Gforward against flange 6, I employ a washer, \V, and a spring, 12, forthat purpose, as in Fig. 4. This arrangement allows the chasers to beadjusted longitudinally while protecting their sockets from dirt andchips.

The operation of my improved threadingtool is substantially the same asthe operation of others of its class, and will be fully understood fromthe description and drawings by those acquainted with said class oftools.

In using either form of tool shown, the alias ers are first adjusted intheir sockets to bring them to the desired diametrical position, andthrown into their Working position, when the required thread is cut inthe usual manner. The motion ofthe tool (or piece being threaded, as thecase may be) is then reversed, which operation acts, by the friction ofthe threads on the chaser-teeth, to throw said chascrs into their openposition, as shown by dotted lines 5. In this position the chaser-teethstand entirely outside of their working position, so that the threadedpiece may be instantly withdrawn withoutwaiting for the tool to be runoff, as by the old way.

Having thus described my invention, I claim- 1. The combination of athreading-tool body, having chaser-sockets inclined to its axis,oscillating chasers in said sockets, a guard covering said sockets andhaving slots through which project the said chasers, and means,substantially as described, for effecting the longitudinal adjustment ofthe chasers in said sockets, substantially as set forth.

2. The combination, in a threading-tool, of a body, A, which haschaser-sockets inclined to its axis, and is threaded for anadjustingnut, oscillating chasers fitted to slide in said sockets, anadj usting-nut fitted to said thread and constructed to bear against oneend of the chasers, and means, substantially as described,

.for keeping the chasers against said nut, substantially as set forth.

GEO. D. TUCKER.

W it nesses:

Framers H. RICHARDS, Gno. A. REYNOLDS.

